Contents

"Nazotoki" is a song composed, sung, and illustrated by Hinata Haruhana. The song was first published on February 13th 2010, with a Vocaloid version illustrated by Abe uploaded on March 13th 2010. It is Hinata Haruhana's second work in 2010, the previous being Haiiro Sekai.

A long version of the song was uploaded on June 14th 2010 by Kagamine Len. It's featured in the album Kikai Shikake no Nazotoki with a Kagamine Len Power version, and also featured on the album Shiro to Kuro no Labyrinth on July 24th 2012; a long version sung by Hinata Haruhana.

A song of the three riddles in the story Umi wa Sono Nazotoki wo Nozomu no ka?, with Haruka, playing the role as the "detective" narrating along the way. It's directly related to the song Nazokake. A novel adaptation of the song "Nazokake" published on July 2014, is also loosely based on the story and songs; with a similar set of characters to UmiNazo, the main difference being the two main characters "Kurono Rin" and "Shirohane Len".